According to practical experience construction site is usually filled up with stocks of construction materials such as lumber, packs of drywalls, etc., as well as construction tools and equipment. Existing drywall installation devices are floor-based and require the floor to be totally unoccupied with anything in order to operate installation equipment safely.
Technologically ceiling panels supposed to be installed first. So, to install for example 5 boards on the ceiling of some room installer often have to remove 25 or so other panels as well as another staff out of his way. It can take much more time and efforts to clean the room prior to installation than installation process itself.
Due to operational complexity and dimensional features of existing drywall installation devices transportation, deployment and usage of it contribute to efficiency losses as well.
As a result many installers prefer or forced to do drywall installation manually. However for that one installer likely will not be able to do most of the job on his own, not speaking of physical efforts required for that.
Shortcomings mentioned above reveal some space for improvement.